Im not out on this right now.... the s10+ beats a base xo and ps4 but the x1x and ps4 pro muddened the water regarding my estimation.
Because if the next gen is only a bit stronger then the x1x or pro the phones are the way to go, expecially with stadia aswell in mind.
Also, wouldn't be so sure about an S10+ beating the XBO in gaming.
The CPU should do better due to being more modern and the higher clock speed, the GPU is powerful and it looks mighty fine on RAM... but not necessary on it's bandwidth. The Snapdragon 855 and the Exynos 9820 (the S10+ has 2 different chips depending on where you live) both have just over 34GB/s of bandwidth, just half of what the OG XBO had (and 1/8 of the One S, and that was already considered to limiting and choking down it's performance.
In fact, it is a more general problem in the smartphone industry, theoretical performances are keeping going up but the bandwidth isn't following suit, choking the actual performance increases down a lot.
The Nintendo eShop rating Thread: http://gamrconnect.vgchartz.com/thread.php?id=237454